Biology subjects

Brandao, J. R.

Publications and source records attributed to Brandao, J. R..

3 recordsLinked to original sources

bioRxiv2025

Assessing the effects of fertilisation on the yield, protein, and oil content of soybean seeds: a metadata analysis

For a comprehensive study on balancing yield and grain composition, a meta-analysis of 48 peer-reviewed studies evaluated the effects of soil and foliar fertilization on soybean (Glycine max L.) yield, protein, and oil content. The metadata includes fertilizer type, application method, yield (kg ha-1), and concentration of protein (%) and oil (%). The data show that foliar and soil N fertilization increased grain yield by 13.7% and 14.2%, respectively (p < 0.05), compared to the control. However, it did not significantly affect the protein (38.4 {+/-} 3.4%) or oil (20.2 {+/-} 2.3%) content. High variability in experimental designs and the underrepresentation of foliar strategies make it difficult to draw broad conclusions. These findings showed the need for standardized field and controlled trials to balance increased yield with quality and to guide nutrient management.

plant biology↗

bioRxiv2025

Resolving the Foliar Calcium Mobility Paradox: Enhancing Foliar Calcium Transport in Tomato Using Osmotic Regulators

Highlight- In vivo XRF measurements in the petiole confirmed Sr transport to distal tomato tissues. - XRF imaging revealed the distribution of Sr in tomato fruits following foliar application. - Foliar formulations supplemented with osmotic regulators improved Sr absorption and translocation. - Sucrose enhanced both short- and long-distance transport of Sr to tomato fruits. - Sucrose significantly enhanced Sr{superscript 2} accumulation in seeds and the apical mesocarp, the regions most affected by Ca deficiency symptoms The study demonstrates a novel approach for enhancing phloem transport to fruit of foliar-applied Ca Calcium (Ca) deficiency can impair fruit development even under optimal soil Ca levels due to its transpiration-dependent transport. Reduced fruit transpiration may limit Ca delivery to fruits, leading to lower Ca content in the fruit and diminished quality. Foliar application of Ca offers a potential strategy to mitigate these effects; however, its low mobility in the phloem often limits treatment efficacy. To address this, we employed X-ray fluorescence spectroscopy (XRF) to investigate the penetration and transport of foliar-applied Ca, using strontium (Sr) as a physiological tracer. Additionally, we evaluated the influence of osmotic regulators, sucrose, mannitol, glycerol, and potassium, on Ca transport. Results showed that Sr was effectively translocated to distal tissues. While potassium and mannitol had no significant impact on transport kinetics, sucrose and glycerol enhanced Sr movement. XRF imaging of leaf tissue revealed that Sr was primarily transported through the apoplast toward the leaf margin. Moreover, foliar application of Sr combined with sucrose significantly increased Sr accumulation in seeds and in the apical portion of tomato fruits. These findings suggest that, contrary to the common assumption of limited foliar Ca mobility, sucrose, can acts as an effective osmotic regulator, enhancing both short-range movement within leaf tissue and long-distance translocation to fruit.

plant biology↗

bioRxiv2022

May mineral composition trigger or limit the protein content in soybean (Glycine max (L.) Merrill) seeds? Insights from a survey on 95 varieties cultivated in Brazil

Background and AimsSoybean (Glycine max (L.) Merrill) stands out as the major source of protein and oil for human and animal nutrition. Nevertheless, the increase in soybean yield has been accompanied by a reduction in its protein content in the last few decades. Since this might be influenced by the elemental composition of the seeds, we herein aimed at determining the profile of mineral nutrients and protein of 95 soybean varieties broadly cultivated in Brazil, the worlds biggest soybean producer and exporter, to identify possible nutritional triggers for the protein content. MethodsEnergy dispersive fluorescence spectroscopy (EDXRF) was employed to determine the concentration of macro, i.e., (K), phosphorus (P), sulphur (S), calcium (Ca), and micronutrients, i.e., iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu). The protein content was evaluated in soybean seeds by the Dumas method. The correlational and clustering assessment between nutrients and protein were determined through both univariate and multivariate non-parametric tests. ResultsBoth protein and nutrient concentrations are not homogeneous across soybean seed varieties, and a clear positive association between protein and sulphur (S), zinc (Zn), and manganese (Mn) concentrations were observed. ConclusionThe recorded results suggest that sulphur (S), zinc (Zn), and manganese (Mn) are the limiting nutrients for higher protein content in soybean seeds.

plant biology↗